Photo credit: Jorgen Hog The Upper Guadalupe River: Stewarding a Hill Country Icon Prepared for The Guadalupe River Association ©June 2017 Charlie Flatten, Program Manager Hill Country Alliance Summary The Upper Guadalupe River is one of the iconic rivers of the Texas Hill Country, originating from an aquifer underlying the eastern Edwards Plateau, and cutting canyons for 187 miles through rolling limestone hills. Before eventually reaching the confines of Canyon Dam in central Comal County the Upper Guadalupe drains nearly 1,427 square miles of seven counties. For millennia, the river has provided dependable quantities of clean water for fish, game, and humans. This report summarizes research and stewardship efforts in the Upper Guadalupe River basin. Understanding the river’s unique characteristics, the diverse land uses that take place within the basin, and the wide variety of stakeholders interested in its long-term sustainability will inform future efforts to protect its economic and ecologic vitality. There are a variety of organizations, agencies, business, and individuals invested in the future health and protection of the Upper Guadalupe River. Coordinating efforts between these groups will ensure efficiency, enhance community outreach and education efforts, and improve our overall understanding of the river. This report first summarizes some of the physical, geological, hydrological, ecological, historical, cultural, and demographic characteristics of the Upper Guadalupe basin and its stakeholders. It is sourced from a variety of programmatic reports and scientific journal articles that have been written about the river and the wider Edwards Plateau region. The review goes on to list research needs, challenges to the health of the river, and opportunities for collaboration. Existing and ongoing efforts are then summarized with a list of organizations and agencies that are actively working within the basin. Guadalupe Bass (Micropterus treculii) Illustration by Joe Tomelleri 2 Figure 1: Topographic Map of the Upper Guadalupe River 3 Table of Contents Introduction………………………….…….…………………………………………………………………………………………… 5 Natural and Cultural History….…….……………………………………………………………………………………………6 Geography………………………………………………………………………………………………………………………………..6 Geology, Topography and Hydrology…...………………………………………………………………………….….…..8 Climate ……………………………………….……………………………………………………………………………………… … 12 Water Resources ………………….…….………………………………………………………………………………… ……… 13 Species and Ecology ……………...…….………………………………………………………………………………………… 21 Land Uses ……………………………...…….…………………………………………………………………………………………22 Demographics …………………………….…………………………………………………………………………………..…….23 Brush Control ……………………...…….…………………………………………………………………………………………25 Conserved Lands, Parks, And Public Access…………………………………………………………………...…………26 Built Environment……………………………………………………………………………………………………...…………….28 Research Needs ….…………………………...………………………………………………………………………...…………..30 Threats to Basin Health……………….………………….……………………………………………………….……………….32 Basin Resources ………………………...……………….…………………………………….………………………….………….37 Reference List …………………………………………………………………………………………………………….…………….44 Historical USGS Flow-Rate Data Index……………………………………………………………………………………….49 4 Introduction The Texas Hill Country’s iconic Upper Guadalupe River flows from its headwaters to Canyon Lake providing economic benefits through enhanced property values, sport fishing, recreation opportunities, and municipal, agricultural, and wildlife water supplies. Those benefits are dependent on reliable river flow and high-quality water. The Guadalupe River is considered by many to be Texas’s most scenic waterway. The tourism industry values the Guadalupe for its cool blue waters and natural settings; cities along its course use its clean water supplies, and fish and wildlife depend on its reliable flow. As the Guadalupe wanders through mostly rural sections of the Hill Country, it provides excellent habitat for wildlife and humans alike. Understanding the river is crucial to protecting its ability to provide a high-quality habitat and this report is meant to identify and inform urban and rural stakeholders of its capabilities, limitations, and requirements for a sustainable future. Currently along this stretch of river, scientific data gathering including base-flow, gain/loss measurements, peak flow, and water quality are valuable, yet insufficient to tell the full story of recharge features, springs, threats to water quantity, sources of water quality degradation and priority conservation areas. The Guadalupe River Association has recognized a need to identify basic hydrologic data gaps, and to expand opportunities for constructive collaboration on the Upper Guadalupe River basin as defined from its uppermost reaches to Canyon Lake. Figure 2: Overview of Guadalupe basin from headwaters to bay 5 Natural and Cultural History The name Guadalupe, or Nuestra Señora de Guadalupe, was applied to the river in 1689 when the stream was named by Alonso De León. The artifacts that have been found in the Guadalupe River valley, suggest that the area has supported human habitation for several thousand years. The peoples encountered by early explorers belonged to the indigenous Tonkawa, Waco, Lipan Apache, and Karankawa tribes. These early inhabitants were gradually displaced by settlers from Mexico, Europe, and the United States (Smyrl 2017). Early written accounts of the Upper Guadalupe River basin come from the 17th century when Spanish explorers were just beginning to enter the area. For the most part, those explorers chose to stay out of the Hill Country region because of heavy “brushwood” found at the edges of the hills in what is now Comal County, and to avoid conflicts with resident Native Americans (Weniger 1984). By the early-19th century, scouts and German settlers were making their way deeper into the Guadalupe River basin establishing permanent settlements and towns. These early pioneers sent accounts of thick cedar (Ashe Juniper) and oak forested valleys in the uplands of the basin. Jean Louis Berlandier described what he saw in the Guadalupe basin near present day Hunt in 1828: “The forests are very heavy. There is an abundance of cedar and various oaks scattered about in groupings...we went out... to survey the cedar forest to the east...” (Nelle, 2012). “Pre-1860 eyewitness accounts provide compelling evidence that the Hill Country of Texas was not predominantly open grassland prior to European settlement as is widely believed. The Hill Country did contain areas of open grassland, but these were in combination with large areas of savanna, shrubland, woodland and forest. The landscape was complex and diverse, not uniform or homogeneous. The arrangement of different soils and topography, mixed with the pruning effects of fire, resulted in what can only be called a dynamic mosaic of many vegetation types. There is ample evidence from history that the mosaic of the Hill Country was predominantly wooded” (Nelle, 2012). Geography The Upper Guadalupe River flows through three counties and its basin covers an area of approximately 1,427 square miles (913,280 acres) of the Texas Hill Country. It flows in a roughly easterly direction beginning in far-western Kerr County, through Kendall County and into Comal County. The basin’s maximum elevation is 2,424 feet above sea level (MSL), and the lowest is 822 feet MSL giving it a relief of 1,602 feet over its 187 river-mile length. The north-western side of the drainage basin is approximately 2 miles west of the point where Kerr, Kimble, and Gillespie Counties meet. The far western extent of the basin meets the western boundary of Kerr County at the Real County line. The basin occupies the majority of Kerr and Kendall Counties with the exception of the far northern and southern portions of those counties, and most of the northwestern portion of Comal County. Additionally, the basin covers approximately 33 square miles of the southwest corner of Gillespie County, a smaller portion of northern Bandera County, and about three square miles of the southernmost point of Blanco County (USGS 1982). 6 Figure 3a: Headwaters to Comfort administered by the Upper Guadalupe River Authority (GBRA 2017) For administrative and water quality testing purposes, the Upper Guadalupe River basin is divided into eastern and western halves. The western half begins at the Real-Kerr County line as a series of springs and seeps, and terminates at the downstream edge of Comfort Texas [Figure 3a]. The Guadalupe’s North and South Fork tributaries join at Hunt to form the main channel of the Guadalupe and are then joined at Ingram by the north-south oriented Johnson Creek. Low water crossings and low dams create a series of pools from Hunt, and Mountain Home through the downstream portion of Kerrville before the river begins to run free again. The eastern half begins east of Comfort with a boundary at Canyon Dam [Figure 3b]. 7 Figure 3b: Comfort to Canyon Dam administered by the Guadalupe Blanco River Authority (GBRA 2017) Geology, Topography, and Hydrology “Best known as the Hill Country, the Edwards Plateau is more than scenic hills west of IH-35. Wholly contained within the Texas borders, at a crossroads of arid grasslands, woodlands, and brushlands, its habitats are supported by unique geohydrology. Geology and hydrology are two of the greatest influences in this region on wildlife and fish distribution, rarity, and endemism.” (TPWD 2012) The underlying geology of the Edwards Plateau region is essential to informing our